The present invention relates to a method of calculating of a position of a first radio station intended to be connected to a second radio station, using measurements of a radio signal, called location signal, sent by one of the first and second radio stations, called emitting radio station, to the other of the first and second radio stations, called receiving radio station, and propagated to the receiving radio station along a plurality of radio paths including a shortest radio path.
It also relates to a communication network comprising a first radio station intended to communicate with a second radio station which may move relative to the first radio station, at least one of the first and second radio stations being configured to send a radio signal, called location signal, propagated to the other one of the first and second radio stations through a plurality of radio paths including a shortest path, and the other one of the first and second radio stations being configured for making measurements of the location signal and for calculating a position of the second radio station from the measurements.
It also relates to a radio station intended to be used in such a communication network.
Such positioning methods are notably described in the article xe2x80x9cOverview of Radiolocation in CDMA Cellular Systemsxe2x80x9d from James J. Caffery, Jr. and Gordon L. Stxc3xcber published in IEEE Communications Magazine in April 1998. A position can be derived from measurements of signals, for example propagation time. The problem is that the signals which are detected at the receiving station and which are used for such measurements often correspond to reflected radio paths which are longer than direct radio paths. This results in an inaccurate position.
One of the aims of the invention is to propose a method of calculation of a position of radio station with improved accuracy.
This object is achieved with the method described in claim 1 of the present application. As the energy of received signals is increased, the level of the signal received via the direct path is sufficiently high for this signal to be detected by the receiver.